1. Field of the Invention
The present invention relates to a threshold value data setting device, method, and program, and an image forming system which set threshold value data for creating a binary image signal representing the shape and arrangement of respective dots constituting an image based on a continuous tone image signal.
2. Description of the Related Art
In a printing field, computer to plate (CTP) which directly forms a printing plate through electronic data without generating an intermediate product is becoming widespread. Typically, in a process of forming a printing plate, screening processing including a systematic dither method is executed for a continuous tone image signal. Various methods of determining threshold value data in consideration of all or a part of the characteristics of a printing system in order to obtain high-image quality printed matter have been hitherto suggested.
JP2002-368995A suggests a method which determines a threshold value array causing hardly any occurrence of moire by sequentially performing (1) pseudo generation of dots and (2) evaluation of a specific frequency component of a density pattern including the dots.